JP2020507488A - Method for manufacturing a grinding tool and a grinding tool - Google Patents

Abstract

In a method for manufacturing a grinding tool, a tool base body (4) is provided which has an adhesive surface (24) formed three-dimensionally by applying a binder. The tool base body (4) is positioned such that the bonding surface (24) is located in an electrostatic field (E) between the first electrode (5) and the second electrode (6). The abrasive grains (8, 9) are moved in the electrostatic field (E) such that the abrasive grains (8, 9) move toward the bonding surface (24) based on the electrostatic field (E) and remain adhered there. Carried in. A grinding tool manufactured in this manner has a three-dimensionally formed abrasive layer (25). The manufacture of grinding tools is simple, flexible and economical. The grinding tool has an arbitrarily shaped abrasive layer (25) and can be used in a wide variety of applications with high scraping capacity and long service life.

Description

  The present invention relates to a method for manufacturing a grinding tool and a grinding tool.

  Hand-handed grinding tools (grinders) for surface finishing are manufactured with bonded abrasives (abrasives) or with overcoated abrasives. From patent document 1 (which corresponds to patent document 2), for example, a grinding body combined with a synthetic resin, that is, a rough grinding disk (flap disk) having a combined abrasive is known. On the other hand, from U.S. Pat. No. 5,077,098 (corresponding to U.S. Pat. No. 5,059,086), a flap disk is known which includes a support plate provided with a grinder slice. The grinder flakes are made from an overcoated abrasive (grinding means) and include abrasive grains bonded to the base by a binder. Overcoated abrasives can be used with respect to bonded abrasives with respect to the use of manually driven grinding tools, e.g. higher shaving capacity and longer service life and associated lower labor costs, reduced shaving time. It has various advantages, such as reduced labor and reduced noise and vibration loading.

  In a rough grinding disc known from US Pat. No. 6,037,097, each of a plurality of grinder flakes is bent around the outer peripheral edge of the support plate, so that each of the grinder flakes is three-dimensional (three-dimensional). To form an abrasive layer formed on the substrate. This allows the rough grinding disc to have high scraping capacity in a wide variety of abrasive uses. The disadvantages are that the rough grinding discs are expensive to manufacture and that there is a risk of damaging the respective abrasive layers when bending the grinder flakes, so that only three-dimensional The point is that the formed abrasive layer cannot be produced.

WO 2009/138 114 A1 US 2011/0065369 A1 EP 2 130 646 A1 US 2009/0305619 A1

  The present invention is based on the first task of creating a method that enables the production and high shaving capacity of grinding tools with an arbitrarily formed abrasive layer in a simple, flexible and economical manner. I have.

  The present invention further addresses the second problem of creating a grinding tool that is simple to manufacture and that can be used flexibly and that has an optionally formed abrasive layer and has a high shaving ability. Is based on

  The first object is solved by a method having the features of claim 1. By applying a binder to the tool base body (coating), a three-dimensionally shaped adhesive surface is created according to the shape of the tool base body or the shape of the base body surface of the tool base body. You. By positioning a tool base body having an adhesive surface in an electrostatic field and incorporating the abrasive grains into the electrostatic field, the tool base body is directly layered with the abrasive grains. Abrasive particles that are entrained in the electrostatic field move along the force lines in the direction of the bonding surface and remain adhered to the tool base body when in contact with the bonding surface or binder, so that the abrasive particles are attached to the bonding surface. A correspondingly three-dimensionally formed abrasive layer is formed. A plurality of electrodes are formed from a conductive material to create an electrostatic field. Since the abrasive grains are applied directly to the tool base body and thus the tool base body forms the basis, the grinding tool is simpler, more flexible and economical compared to using a coated abrasive. In addition, it can be manufactured. The abrasive layer can be produced by providing the desired tool base body and applying the three-dimensionally formed abrasive layer to the binder in a flexible manner. As the abrasive grains move along the force lines, the abrasive grains are applied on the tool base body or the bonding surface in a desired manner, depending on the extension of the force lines and the positioning of the tool base body. High grinding ability and long service life of the grinding tool are guaranteed. The abrasive grains can move toward the bonding surface using or against gravity in an electrostatic field.

  The tool base body is configured as a single layer or a multilayer. The tool base body includes at least one material from the group consisting of vulcanized fiber, polyester, glass fiber, carbon fiber, cotton, plastic, and metal. The tool base body may have a coated abrasive. The tool base body has elasticity in at least some areas and / or has no elasticity in at least some areas. The tool base body may have a hub or shaft for applying tension and for rotating the grinding rear.

  Binders are a group of materials consisting of thermosets, elastomers, thermoplastics, and synthetic resins. The binder is in particular a thermosetting plastic such as a phenolic resin or an epoxy resin. The phenolic resin is, for example, resol or novolak. The binder may be applied on the tool base body in any desired manner.

  The abrasive has a geometrically specified shape and / or a geometrically unspecified shape. The abrasive grains include at least one material selected from the group consisting of ceramics, particularly corundum such as zirconium corundum, diamond, cubic boron nitride (CBN), silicon carbide, and tungsten carbide.

  The abrasive grains can be applied in a single layer or in multiple layers, so that the tool base body has at least one three-dimensionally shaped abrasive layer. When a plurality of abrasive layers are formed, a binder is applied to the underlying abrasive layer each time, and the subsequent abrasive layer is applied using an electrostatic field in the manner described above. The binder thus forms a base bond between the tool base body and the abrasive layer applied thereon and also forms an intermediate bond between the two abrasive layers.

  The bonding surface or abrasive layer may be three-dimensionally shaped in any manner, for example, curved and / or with a plurality of planes aligned with one another, such as planes extending obliquely with respect to each other. Is molded. The curved formation allows, for example, the treatment of fillet welds and / or the treatment of edges. With the plurality of planes extending obliquely to each other, the abrasive grain layer forms a chamfered portion that enables rough finishing (rough cutting) or plane processing.

  The method according to claim 2 guarantees a simple, flexible and economical production. The curved adhesive surface or the curved abrasive layer makes it possible in particular to produce grinding tools for the treatment of fillet welds and / or the treatment of edges. The bonding surface or abrasive layer is in particular convexly and / or concavely curved. The bending direction is defined, for example, in relation to the longitudinal central axis of the tool base body and / or in relation to the tensioning side (tensioning side) directed towards the tool drive of the grinding tool. The bonding surface or abrasive layer is, for example, cylindrical or spherical.

  The method according to claim 3 guarantees a simple, flexible and economical production. The relative movement of the tool base body with respect to at least one of the two electrodes ensures a reliable and even coating of the abrasive on the bonding surface, and thus ensures an even layer of abrasive. You. The movement changes at least the orientation, spacing, and / or length of one of the electrodes. The movement takes place, in particular at least partially, while the abrasive grains move towards and adhere to the bonding surface. The tool base body is moved, for example, using a mounting device.

  The method according to claim 4 guarantees a simple, flexible and economical production. By directing the longitudinal center axis of the tool base body in different directions, it is possible to produce a complicatedly formed abrasive layer.

  The method according to claim 5 guarantees a simple, flexible and economical production. The rotation of the tool base body about the longitudinal central axis allows the abrasive grains to be applied at high speed and evenly. This rotation takes place in particular during the application of the abrasive grains. In particular, the rotation speed is adjustable, so that the abrasive grains can be coated in a simple and flexible manner. The rotation speed is adjusted, for example, according to the size and / or mass of the applied abrasive grains and / or the desired thickness of the abrasive layer.

  The method according to claim 6 guarantees a high chipping capacity and a long service life. The lines of force of the electrostatic field enter and exit perpendicular to the surface of the electrode, so that the extension of the lines of force can be adjusted by the surface shape, length, and / or orientation of the electrode. By properly positioning the bonding surface with respect to the force lines, a plurality of abrasive grains are applied on the bonding surface in a desired orientation. Based on the orientation, the grinding tool has a high scraping capacity and a long service life.

  The method according to claim 7 guarantees a simple, flexible and economical production. With the aid of the transport device, the abrasive particles are automatically transported into the electrostatic field, from which they are transferred to the bonding surface due to the electrostatic field. The transport device can be driven, for example, continuously or intermittently (periodically). In particular, the transport device is driven according to the movement of the tool base body. For example, the transport device is synchronized with the movement of the tool base body. In particular, the transfer speed of the transport device is adjustable.

  The method according to claim 8 guarantees a simple, flexible and economical production. The transport band allows the formation of a seamless (closed loop) transport device in a simple manner. The transport band is guided, for example, around at least two conversion wheels, which allows, for example, a continuous drive of the transport device. The transport band is in particular formed electrically insulated.

  The method according to claim 9 guarantees a simple, flexible and economical production. With the first electrode being arranged below the transport area in the direction of gravity, the abrasive grains are brought into the electrostatic field in a simple manner. The transport area is formed, for example, by the surface of the transport band. The first electrode is disposed fixedly or displaceably. The first electrode is particularly formed in a plate shape. In particular, the plate-shaped electrodes basically extend parallel to the transport band and extend.

  The method according to claim 10 guarantees a simple, flexible and economical production. At least one metering device supplies the abrasive grains directly to the electrostatic field and / or the transport device. At least one metering device meters and dispenses the abrasive to be applied. In particular, at least one metering device is arranged upstream of the transport device and supplies abrasive particles to the transport device. Using at least one metering device, an abrasive mixture (abrasive mixture), in particular composed of abrasive grains, is supplied. Within the abrasive mixture, the abrasive grains may vary in size, shape and / or material. Since the abrasive mixture can be mixed, for example, before being fed into the metering device, it is possible to feed the abrasive grains using just one metering device. Further, a plurality of metering devices may be provided, each of which includes exactly one type of abrasive grain, so that the abrasive mixture is supplied in a flexible manner during supply. Are mixed using a metering device. With at least one metering device, the orientation, the appropriate metering and / or distribution of the abrasive grains is performed.

  The method according to claim 11 guarantees a simple, flexible and economical production. By adjusting the voltage, the electrostatic field is adapted to the abrasive to be supplied.

  The method according to claim 12 guarantees a simple, flexible and economical production. The second electrode is minimally adapted to the tool base body because the tool base body itself forms the second electrode. Since the force lines enter and exit the tool base body perpendicular to the bonding surface, the abrasive grains are directed in a concise manner onto the complex three-dimensionally shaped bonding surface. Can be applied. The tool base body is conductive, at least in part or layer by layer. Since the tool base body forms the second electrode, an abrasive layer that forms an undercut with the tool base body can also be produced. In other words, the tool base body or the second electrode remains on the grinding tool and does not need to be removed.

  The method according to claim 13 guarantees a simple, flexible and economical production. The tool base body forms at least one conductive layer, so that the tool base body itself forms the second electrode. The conductive layer is arranged in particular on the surface of the base body, for example on the front and / or the back of the tool base body and / or inside. The tool base body may be formed, for example, from a completely conductive material.

  The method according to claim 14 guarantees a simple, flexible and economical production. The conductive binder simplifies the abrasive coating, since the formation of a blocking field is avoided, and is particularly advantageous with the tool base body when the tool base body forms the second electrode. Acting jointly.

  The method according to claim 15 guarantees a simple, flexible and economical manufacture, together with a high shaving capacity and a long service life. The tool base body itself forms the second electrode with the conductive material.

  The method according to claim 16 guarantees a simple, flexible and economical production. The fact that the second electrode is formed separately from the tool base body allows the second electrode to be used for producing a plurality of grinding tools. Using the separated second electrode, abrasive grains can be applied to a tool base body made of an arbitrary material, particularly a tool base body made of a non-conductive material.

  The method according to claim 17 guarantees a simple, flexible and economical production, with a high chipping capacity and a long service life. Due to the second electrode being at least partly shaped correspondingly to the tool base body, the surface of the second electrode and the adhesive surface extend substantially parallel to one another, so that the field lines Are oriented substantially perpendicular to the bonding surface. Thus, the abrasive grains can be oriented in a desired manner when adhering to the adhesive surface, thereby enabling high scraping capacity and long service life. The second electrode is, for example, formed completely corresponding to the tool base body and is arranged on the tool base body over the entire surface. Furthermore, the second electrode is shaped correspondingly to the tool base body, for example in a partial area, and is moved relative to the tool base body during the application of the abrasive grains, wherein the second electrode is In particular, the adhesive surface is substantially completely covered during the transfer.

  The method according to claim 18 guarantees a simple, flexible and economical manufacture, together with a high shaving capacity and a long service life. The abutment of the second electrode against the tool base body causes the surface of the second electrode to extend substantially parallel to and / or near the bonding surface, so that the abrasive grains are not as desired. Is applied to the adhesive surface with the orientation of This allows for high scraping capacity and long service life.

  The second object is achieved by a grinding tool having the features of claim 19. The advantages of the grinding tool according to the invention correspond to the advantages of the manufacturing method according to the invention already described. The grinding tool can also be developed, in particular, by at least one feature of at least one of the claims. The abrasive layer is three-dimensionally formed in any manner. For example, it may be formed of a plurality of mutually coordinated planes, such as curved and / or planes extending, for example, at an angle to one another. The curved shape allows, for example, a fillet welding process and / or an edge process. With the plurality of planes extending obliquely with respect to each other, the abrasive grain layer forms a chamfer that enables rough finishing (rough cutting) or plane processing.

  The grinding tool according to claim 20 can be used flexibly. By means of a curved abrasive layer, in particular a convexly and / or concavely curved abrasive layer, the fillet welding process and / or the edge treatment can be performed in a flexible manner.

  The grinding tool according to claim 21 guarantees a flexible use with a high shaving capacity and a long service life. Because the abrasive grains are adjusted (directed) towards the tool base body, i.e. in the three-dimensionally formed abrasive layer, the grinding tool has a high shaving capacity and a long service life in different uses. .

The grinding tool according to claim 22 guarantees a flexible use with a high shaving capacity and a long service life. Depending on the size of the abrasive grains, the grinding performance of the grinding tool is adjusted in a desired manner. By means of an abrasive mixture consisting of large or coarse-grained abrasive grains and small or fine-grained abrasive grains, in particular, the targeted adjustment of the cutting space (chip space) and thus the chipping capacity and the grinding surface or abrasive layer Can have a positive effect. Fine abrasive has a maximum dimension D _1, while the coarse particles have a maximum dimension D _2. Between them, D ₁ ≦ D ₁ holds.

The grinding tool according to claim 23 guarantees simple production and flexible use. The abrasive grains are formed of fine particles. Fine-grained abrasive grains are used as fillers (filled grains), particularly in a state of being combined with coarse-grained abrasive grains. The fine particle abrasive is applied before, with, and / or after the coarse particle abrasive. The fine grain abrasive is applied electrically and / or mechanically. Abrasive the coarse particles have a maximum dimension D _2, respectively, in particular, D ₁ ≦ D ₁ is satisfied.

The grinding tool according to claim 24 guarantees simple production and flexible use. The coarse-grained abrasive grains are particularly applied (coated) with the fine-grained abrasive grains. In this case, the abrasive grains of coarse particles form the main grains, and the abrasive grains of fine particles form the filling grains. The packed particles are made of, for example, brown alumina (usually corundum). The abrasive grains of coarse particles are made of, for example, ceramic. The abrasive grains of fine particles each have a maximum dimension D ₁ , and in particular, D ₁ ≦ D ₁ holds.

  The grinding tool according to claim 25 guarantees a flexible use with a high shaving capacity and a long service life. After application of the abrasive layer, the grinding tool or binder (base bond) is cured in a furnace in the usual manner. A binder is applied over the abrasive layer to form at least one cover bond fixture and possibly an additional cover layer. By means of the cover connection fixing part or the cover layer, the scraping ability and the service life are improved. The binder is configured correspondingly to the binder, for example to form an adhesive surface, and in a conventional manner comprises a filler capable of polishing, such as cryolite or potassium tetrafluoroborate. May be. The cover layer or the cover connection fixing part is hardened especially in an oven.

  Further features, advantages and details of the present invention result from the following description of several embodiments.

1 shows a schematic view of an apparatus for producing a grinding tool by applying a tool base body with abrasive grains using an electrostatic field between two electrodes. FIG. 2 shows an enlarged cross-sectional view of the tool base body and associated electrodes of FIG. 1 according to a first embodiment. The finished grinding tool shows a pharmaceutical cross section. FIG. 4 shows a cross-sectional view of a tool base body and associated electrodes according to a second embodiment. FIG. 4 shows a sectional view of a tool base body formed as an electrode according to a third embodiment. FIG. 7 shows a sectional view of a tool base body formed as an electrode according to a fourth embodiment.

  Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. The device 1 for producing the grinding tool 2 comprises a handling device 3 for handling and positioning the tool base body 4, a first electrode 5 and an associated second electrode 5 for generating an electrostatic field E, a transport device 10 And a charging device (surveying device) 7 for supplying abrasive grains 8 and 9 to the apparatus.

The transport device 10 includes a seamless (closed loop) transport band 11 that is tensioned using two transfer rollers 12,13. The conversion roller 12 is driven to rotate using, for example, an electric drive motor 14. The transport band 11, the portion that is disposed above the turning rollers 12 and 13 with respect to gravity F _G forms a transfer region 15 which extends in a horizontal x-direction and a horizontal y-direction.

The charging device 7 is disposed upstream of the electrodes 5 and 6 in the transport device 16. The first electrode 5 is disposed is formed in the plate shape and the lower portion of the lower or the transport regions 15 of the top member of the conveyor band 11 in the direction of gravity F _G. The second electrode 6 on the opposite is disposed above the conveyor band 11 or the transport regions 15 with respect to gravity F _G. The second electrode 6 is therefore spaced from the first electrode 5 in the vertical (vertical) z-direction, so that the transport area 15 extends between the electrodes 5,6. The x, y, and z directions form a Cartesian coordinate system.

  The functions of the device 1 are described below.

  The second electrode 6 is formed separately from the tool base body 4 and is formed corresponding to the tool base body 4. The second electrode 6 is fixed to the handling device 3. The tool base body 4 is held by using the handling device 3 such that the second electrode 6 is basically in contact with the back surface 17 of the tool base body 4 over the entire surface. The handling device 3 holds the tool base body 4 mechanically and / or pneumatically, for example. A voltage U is applied between the first electrode 5 and the second electrode 6, which voltage U is generated by a power supply 18 and is adjustable.

  The tool base body 4 has a three-dimensional (three-dimensional) shape. In the inner region 19, the tool base body 4 is formed in the shape of a disk and has, for example, a hub 20. Alternatively, the tool base body 4 may have a shaft instead of the hub 20. Configurations without hub 20 or shaft are also possible. On the other hand, the tool base body 4 is curved in a region 21 surrounding the region 19.

  A bonding agent 23 is first applied to the front surface 22 away from the second electrode 6, so that the bonding agent 23 arranged on the tool base body 4 forms a three-dimensionally shaped adhesive surface 24. I do. The binder 23 is, for example, a resin, particularly a phenol resin. The tool base body 4 is made of a usual material such as Vulcan fiber or polyester. The binder 23 is applied, for example, manually or using the handling device 3. The tool base body 4 is immersed in the bonding agent 23 at the front face 22 using, for example, the handling device 3.

The tool base body 4 is then positioned above the first electrode 5 in the z-direction using the handling device 3, so that the bonding surface 24 is partially located in the electrostatic field E between the powers 5, 6 You. The field lines exit the surface of the first electrode 5 and enter perpendicular to the surface of the second electrode 6 so that the field lines essentially extend vertically through the adhesive surface 24. This is illustrated in FIG. 2 for f ₁ , f ₂ and f ₃ .

Using the transfer device 10, the abrasive grains 8, 9 are transferred to the electrostatic field E in order to form a three-dimensionally shaped abrasive layer 25. For this purpose, the charging device 7 prepares, for example, a mixture of fine abrasive grains 8 and coarse abrasive grains 9. Each of the abrasive grains 8 fine particles have a maximum dimension D _1, for at least 80% of the abrasive grains 8, especially to at least 90%, also particularly for at least 95%, 1 μm ≦ D ₁ ≦ 5000 μm, in particular 5 μm ≦ D ₁ ≦ 500 μm, and in particular 10 μm ≦ D ₁ ≦ 250 μm. In contrast, each of the abrasive grains 9 have a maximum dimension _{D 2,} for at least 80% of the abrasive grain 9, in particular to at least 90%, also with respect to particular at least 95%, 1 [mu] m ≦ D ₂ ≦ 5000 μm, in particular 150 μm ≦ D ₂ ≦ 3000 μm, and especially 250 μm ≦ D ₂ ≦ 1500 μm. In particular, D ₁ ≦ D ₂ holds. Therefore abrasive 8,9 has a maximum dimension D ₁ or D ₂ in the mixture, the maximum size of the mixture is referred to as D in common. Thus, in the mixture, the abrasive grains 8, 9 have a maximum dimension D, for at least 80%, especially for at least 90%, and especially for at least 95% of the abrasive grains 8, 9 1 μm ≦ D ≦ 5000 μm, especially 10 μm ≦ D ≦ 2500 μm, and especially 100 μm ≦ D ≦ 1000 μm.

  A suitable amount of the abrasive grains 8 and 9 are charged using the charging device 7, supplied to the transport band 11, and distributed thereon. Using, for example, an electric drive motor 14, the transport band 11 is moved in the transport direction 16 together with the abrasive grains 8, 9 arranged thereon, so that the abrasive grains 8, 9 are put into the electrostatic field E. For example, the transfer speed in the transport direction 16 can be adjusted using the electric drive motor 14.

Abrasive 8,9 by the electrostatic field E is moved toward the adhesive surface 24 against the force of gravity F _G, and, along the force lines are directed along the example field lines f _1, f ₂ and f ₃ . When the abrasive particles 8, 9 hit the bonding surface 24, they remain bonded there. An abrasive layer 25 is formed on the tool base body 4 by the bonded abrasive particles 8 and 9. The tool base body 4 is rotated around the central longitudinal axis by means of the handling device 3 in order to apply the abrasive grains 8, 9 uniformly and evenly. Since the fine-grained abrasive grains 8 adhere to the tool base body 4 between the coarse-grained abrasive grains 9, the abrasive grain layer 25 is uniformly formed. In this case, the coarse-grained abrasive grains 9 form the main abrasive grains, and the fine-grained abrasive grains 8 form the filling abrasive grains. The abrasive layer 25 is three-dimensionally shaped or curved, corresponding to the bonding surface 24. Furthermore, the tool base body 4 is moved, if necessary, so that the longitudinal central axis 26 is oriented in different directions with respect to the first electrode 5.

  Since the abrasive layer 25 has been applied to the tool base body 4 until completion, the tool base body 4 together with the binder 23 and the abrasive layer 25 forms a semi-finished product. The semi-finished product is removed from the handling device 3 and placed in a heating device where the binder 23 is cured. The abrasive layer 25 is subsequently provided in a conventional manner with at least the cover fixing part 27 and, if appropriate, the cover layer 31. The cover connection fixing part 27 has, for example, a bonding agent 23 with an additional grind active filler. The cover layer 31 is applied on the cover connection fixing part 27. The cover layer 31 has a binder 23 with a filler which is effective for additional grinding. In this case, the ratio of the filler effective for grinding is particularly larger than the ratio of the cover joint fixing portion 27. The cover connection fixing portion 27 and the cover layer 31 are applied, for example, manually. Subsequently, the cover connection fixing part 27 and the cover layer 31 are cured in the heating device. The binder 23 includes, for example, a phenol resin and chalk. The cover connection fixing portion 27 and the cover layer 31 include, for example, phenol resin, chalk, and cryolite. The humidity during the production takes for example a value between 0% and 100%, in particular a value between 35% and 80%. FIG. 3 shows the completed grinding tool.

  Hereinafter, a second embodiment of the present invention will be described with reference to FIG. Different from the first embodiment, the second electrode 6 is formed smaller than the tool base body 4 and overlaps only a partial area of the tool base body 4. In this partial area, the second power 6 is shaped correspondingly to the tool base body 4, so that the second electrode 6 extends essentially parallel to the bonding surface 24. The second electrode 6 does not abut the back side 17 of the tool base body 4 and is slightly spaced therefrom. While the second electrode 6 is fixedly connected to the handling device 3, the tool base body 4 is rotated around the central longitudinal axis 26 using the handling device 3. Accordingly, the tool base body 4 moves relative to the second electrode 6 by rotation about the longitudinal central axis 26. The abrasive grains 8, 9 move in the region of the electrostatic field E in the direction of the bonding surface 24 and, when they come into contact with the bonding surface 24, remain bonded there. As the tool base body 4 moves relative to the second electrode 6, that is, rotates about the longitudinal central axis 26, the bonding surface 24 is entirely covered in layers with abrasive grains 8, 9. With respect to other structures of the present apparatus 1, the functions of the present apparatus 1 and other structures of the grinding tool 2, the above-mentioned embodiments are pointed out.

The third embodiment will be described below with reference to FIG. Unlike the previous two embodiments, the tool base body 4 itself forms the second electrode 6. For this purpose, the tool base body 4 is made of a conductive material, in particular a metal. The tool base body 4 is made of, for example, aluminum. The tool base body 4 shown in FIG. 5 has a concavely curved region 28 in addition to a flat inner region (center side region) 19 and a convexly curved region 21. The bonding surface 24 is thus three-dimensionally shaped in a complex manner. The applied binder 23 has electrical conductivity in order to avoid a blocking field and to optimize the electrostatic field E. The conductive binder 23 is, for example, a conductive varnish. The force lines f ₁ to f ₃ again extend perpendicularly through the bonding surface 24, so that the abrasive grains 8, 9 are directed in spite of the complexly formed bonding surface 24 and on this bonding surface 24 Applied to Since the longitudinal central axis 26 extends essentially in the xy plane, rotation of the tool base body 4 about the longitudinal central axis 26 ensures that the inner region 19 and the regions 21 and 28 are evenly and evenly ground. The particles 8 and 9 cover the layers. With respect to the further structure and function of the device 1 and with regard to the further structure of the grinding tool 2, the above-described embodiments are pointed out.

  Hereinafter, a fourth embodiment of the present invention will be described with reference to FIG. Regarding the difference from the above-described embodiments, the tool base body 4 includes a base body 29 made of a non-conductive material and a conductive layer (film) fixedly connected to the base body 29. 30. On the basis of the conductive layer 30, the tool base body 4 itself forms the second electrode 6. The layer 30 is, for example, a copper film. The conductive layer 30 is coated with a binder 23, resulting in an adhesive surface 24. The binder 23 may have conductivity. The tool base body 4 has an inner region 19, a convexly curved region 21, and a concavely curved region 28. A chamfered region 32 or a chamfer is disposed between the inner region 19 and the convexly curved region 21. The chamfered area 32 and the inner area 19 are connected at an angle α, where α ≠ 180 °. The chamfered region 32 is used, for example, for roughing or chamfering. As the tool base body 4 rotates about the longitudinal central axis 26, the bonding surface 24 is reliably and uniformly coated in layers with the abrasive grains 8, 9 despite the complex three-dimensional shape. The formed abrasive layer 25 is three-dimensionally formed in a complicated manner on the basis of convex and concave curved portions and on the basis of chamfered portions or chamfered regions. With respect to the further structure and function of the device 1 and with regard to the further structure of the grinding tool 2, the above-described embodiments are pointed out.

  The method according to the invention has a small number of manufacturing steps and in particular avoids deformation of the coated abrasive. The method according to the invention makes it possible to produce a grinding tool 2 with a complex three-dimensionally formed abrasive layer for a plurality of different uses. The grinding capability and the service life of the grinding tool are comparable in the case of the present invention to grinding tools made from overcoated abrasives. The electrostatic application of the abrasive grains 8, 9 makes it possible, in particular, for the abrasive grains 8, 9 to be oriented with their respective longitudinal axes perpendicular to the bonding surface 24 or the surface of the tool base body 4. Becomes This guarantees mutual shaving capacity and long service life. The grinding tool 2 according to the invention also has a lower noise and vibration load and a lower effort in use compared to the combined abrasive.

Reference Signs List 4 tool base body 5 first electrode 6 second electrode 8 (fine particle) abrasive particles 9 (coarse particle) abrasive particles 10 transfer device 11 transfer band 23 binder 24 bonding surface 25 abrasive layer 26 longitudinal central axis 27 cover coupling fixing part 30 conductive layer 31 cover layer E electrostatic field U voltage

Claims (25)

A method for manufacturing grinding tools,
-Preparing a tool base body (4);
Producing a three-dimensionally formed adhesive surface (24) by applying a binder (23) to said tool base body (4);
Positioning the process base body (4) such that the bonding surface (24) is located in an electrostatic field (E) between the first electrode (5) and the second electrode (6). ,as well as,
Bringing the abrasive grains (8, 9) into the electrostatic field (E) as follows, i.e. the abrasive grains (8, 9) are based on the electrostatic field (E) and the bonding surface (24) Toward the electrostatic field (E) so as to move toward and remain bonded to form a three-dimensionally formed abrasive layer (25) at the bonding surface (24). A method comprising the step of bringing in the grains (8, 9). The method of claim 1, wherein
The method according to claim 1, wherein the adhesive surface (24) is curved to form the three-dimensionally shaped abrasive layer (25). The method according to claim 1 or 2,
The method characterized in that the tool base body (4) for forming the three-dimensionally formed abrasive layer (25) is moved with respect to at least one of the electrodes (5, 6). . The method according to any one of claims 1 to 3,
A longitudinal center axis (26) of the tool base body (4) for forming the three-dimensionally formed abrasive layer (25) is in a plurality of different directions with respect to the first electrode (5). A method characterized by being directed. The method according to any one of claims 1 to 4,
The method according to claim 1, characterized in that the tool base body (4) for forming the three-dimensionally formed abrasive layer (25) is rotated around a longitudinal central axis (26). The method according to any one of claims 1 to 5,
The method according to claim 1, characterized in that the abrasive particles (8, 9) adhering to the bonding surface (24) are at least partially adjusted towards the bonding surface (24). The method according to any one of claims 1 to 6,
The method according to claim 1, characterized in that the abrasive grains (8, 9) are transported into the electrostatic field (E) using a transport device (10). The method of claim 7, wherein
The method according to claim 1, wherein the transport device (24) includes a transport band (11). The method according to claim 7 or 8,
The method according to claim 1, characterized in that the first electrode (5) is arranged below a transfer area (15) of the transfer device (10). The method according to any one of claims 1 to 9,
The method characterized in that the abrasive grains (8, 9) are supplied using at least one dosing device (7). The method according to any one of claims 1 to 10,
The method according to claim 1, characterized in that the voltage (U) between the electrodes (5, 6) is adjustable. The method according to any one of claims 1 to 11,
The method according to claim 1, characterized in that the tool base body (4) forms the second electrode (6). The method according to any one of claims 1 to 12,
The method according to claim 1, characterized in that at least one conductive layer (30) is formed on the tool base body (4). The method according to any one of claims 1 to 13,
The method according to claim 1, characterized in that the applied binder (23) is conductive. The method according to any one of claims 1 to 14,
The method according to claim 1, characterized in that the tool base body (4) is formed at least partially from a conductive material. The method according to any one of claims 1 to 15,
The method according to claim 1, characterized in that the tool base body (4) and the second electrode (6) are formed separately from each other. The method according to any one of claims 1 to 16,
The method according to claim 1, characterized in that the second electrode (6) is at least partially formed corresponding to the tool base body (4). The method according to any one of claims 1 to 17,
The method according to claim 1, characterized in that the second electrode (6) is at least partially abutted against the tool base body (4). In a grinding tool including a tool base body (4) and abrasive grains (8, 9),
The abrasive grains (8, 9) being bonded to the tool base body (4) using a binder (23) and forming an abrasive layer (25); and 25) is formed three-dimensionally,
A grinding tool characterized by the following: The grinding tool according to claim 19,
A grinding tool characterized in that the abrasive layer (25) is curved. The grinding tool according to claim 19 or 20,
Grinding tool, characterized in that the abrasive grains (8, 9) are adjusted at least partially towards the tool base body (4). The grinding tool according to any one of claims 19 to 21,
Each of the abrasive grains (8, 9) has a maximum dimension D, and for at least 80% of the abrasive grains (8, 9), in particular for at least 90%, and especially For at least 95%, 1 μm ≦ D ≦ 5000 μm, in particular 10 μm ≦ D ≦ 2500 μm, and especially 100 μm ≦ D ≦ 1000 μm,
A grinding tool characterized by the following: The grinding tool according to any one of claims 19 to 22,
Wherein it has abrasive grains maximum dimension _{D 1} each (8), and, for at least 80% of the abrasive grains (8), particularly at least 90%, in particular at least 95% 1 μm ≦ D ₁ ≦ 5000 μm, in particular, 5 μm ≦ D ₁ ≦ 500 μm, and especially 10 μm ≦ D ₁ ≦ 250 μm.
A grinding tool characterized by the following: The grinding tool according to any one of claims 19 to 23,
Wherein it has abrasive grains (9) maximum dimension _{D 2} is each, and for at least 80% of the abrasive grains (9), particularly at least 90%, in particular at least 95% 1 μm ≦ D ₂ ≦ 5000 μm, especially 150 μm ≦ D ₂ ≦ 3000 μm, and especially 250 μm ≦ D ₂ ≦ 1500 μm,
A grinding tool characterized by the following: The grinding tool according to any one of claims 19 to 24,
Grinding characterized in that the abrasive grain layer (25) is provided with a cover fixing part (27), wherein the cover bonding fixing part (27) is particularly provided with a cover layer (31). tool.

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